This invention generally relates to the art of electrical connectors and, particularly, to an electrical connector assembly which includes a first connector mounted on a second connector having a grounding housing.
Generally, electrical connector assemblies include a pair of connectors or connector components mated or mounted together for running circuits through a connector interface. Conductive terminals typically are mounted in dielectric housings of at least one of the connector components. Often, printed circuit boards are used for various purposes and are connected to the terminals. In some instances, grounding systems are used, including grounding shells or entire grounding housings.
One type of electrical connector assembly includes one or more first connectors, such as a header connector, mounted on a grounding housing or chassis which may be fabricated of die cast metal material, for instance. The header connector includes a dielectric housing mounting a plurality of terminal pins. The header connector is mounted to one side of the grounding housing. The terminal pins extend through the housing, electrically isolated therefrom, and into a printed circuit board on the opposite side of the housing. The printed circuit board has terminal circuit means and ground circuit means on a single side thereof facing the housing. The terminals are connected to the terminal circuit means on the printed circuit board, and the housing is engaged with the ground circuit means on the same side of the circuit board. Other electrical components, such as filter capacitors, may be carried on the printed circuit board and electrically coupled through the terminal circuit means to the terminal pins of the header connector. Finally, other components such as integrated circuit chips, ferrite blocks and an additional printed circuit board may be mounted on the grounding housing on the side thereof opposite the side to which the header connector(s) is mounted.
Various problems are encountered with electrical connector assemblies of the prior art as described above. One problem is by putting both the terminal circuit means and the ground circuit means on the same side of the printed circuit board on the opposite side of the grounding housing, the overall size of the circuit board is unduly large. This takes up considerable space or xe2x80x9creal estatexe2x80x9d on the grounding housing and limits the available area where other components, such as integrated circuit chips, might be mounted. In addition, the more dense the circuitry on the header connector (i.e., the number of terminal pins), the less area is available on the printed circuit board for the ground circuit means.
A major problem with such assemblies is that it is desirable to test the header connector circuitry prior to actual use, such as when filter capacitors are incorporated with the terminal pins of the header connector. With the connector assemblies of the prior art, the entire assembly of the header connector(s) and the grounding housing had to be tested together because the header connector was mounted on one side of the housing and the printed circuit board and capacitors were mounted on the opposite side of the housing. If the assembly failed the test procedure, the entire assembly had to be discarded, including the die cast housing which is rather expensive. It would be desirable to be able to test the header connector(s) by itself before it is mounted on the grounding housing. In fact, it often would be desirable to be able to test the header connector alone at one location before it is even assembled to the grounding housing at another location.
The present invention is directed to solving this myriad of problems in a connector assembly of the character described by incorporating the printed circuit board in the header connector, itself, whereby this self-contained subassembly can be subsequently mounted to the grounding housing, after testing the header connector and even before mounting the connector to the housing at a remote location. The invention also significantly reduces the size of the printed circuit board to thereby increase the available space on the grounding housing, such as for mounting integrated circuit chips or other electrical components.
An object, therefore, of the invention is to provide a new and improved electrical connector assembly of the character described.
In the exemplary embodiment of the invention, the connector assembly includes a first connector having a dielectric housing mounting a plurality of conductive terminals. A second connector includes a grounding housing. A double-sided printed circuit board is sandwiched between the first and second connectors. One side of the printed circuit board has circuit means connected to the terminals of the first connector. A second side of the printed circuit board has ground circuit means connected to the grounding housing of the second connector.
According to one aspect of the invention, the grounding housing of the second connector may be a die cast metal housing which includes a plurality of posts projecting through holes in the double-sided printed circuit board. The holes are plated-through holes, with the posts being connected to ground circuit means on both sides of the printed circuit board.
According to another aspect of the invention, the conductive terminals of the first connector comprise terminal pins extending through holes in the printed circuit board, with the pins being electrically isolated from the ground circuit means on the second side of the printed circuit board. The double-sided printed circuit board is mounted to the first connector by a press-fit of the board over the terminal pins. A plurality of capacitor chips may be coupled, through the circuit means on the one side of the printed circuit board, to at least some of the terminal pins.